This work is a form of computer music that combines existing instruments with computer-generated sounds (electroacoustic sounds). The piano sound is amplified but not specifically processed. The electroacoustic sounds incorporate sound hybrid tones as part of the "structural timbre" that the composer is developing. Structural timbre is a collective term for synthesis techniques comprising three pillars:

• "sound morphing," which involves a gradual transition from one sound to another;
• "sound of sound," where one sound is nested within another; and
• "sound hybrid," which combines characteristics from two or more sounds to create a single, unified sound.

Since these synthesized sounds do not exist in reality, they lead to the expectation of novel timbres, devoid of prior familiarity, and ultimately, new musical tones.

 Furthermore, such sounds are synthesized sounds that occupy an intermediate perceptual space between being heard as a single sound and as multiple sounds, precisely targeting the threshold where they can still be perceived as a unified entity.

 In this work, several sound hybrids are performed. In addition to hybrid sounds combining bird calls (specifically, flycatchers) recorded in June of this year with sine waves, water sounds and metallic percussion sounds were also hybridized with electronic sounds. The most significant hybrid sound quotes the string theme from the composer's orchestral work "Sound of Sound" from the previous year. This theme was originally derived from the composer's recitation of the Iroha-uta, with its pitch mechanically analyzed and subsequently harmonized as a melody. The technical challenge here was to further imbue this string sound with the phonemes of the recited "Iroha-uta," thereby enabling the string instruments to "speak." The intention behind the creation of these synthesized sounds, and by extension, the overarching creative intent of the work, is to address the question of whether making string instruments "speak" would diminish their inherent characteristics (i.e., render them no longer string instruments), result in uninteresting, hoarse sounds, or merely present a superposition of voice and string instrument. The desired answer is a resounding "no," asserting that the outcome is a single, compelling musical tone.

 The phonemes of the Iroha-uta recited are as follows: "Iro wa nioedo chirinuru wo, Waga yo tare zo tsune naramu. Ui no okuyama kyo koete, Asaki yume miji ei mo sezu."